1. Field of the Invention
The present invention relates to a key switch, especially suited for use on a keyboard for a notebook computer, employing a flexible member to produce a sense of two-step touch control, and to restore the key switch to its original position without the use of rubber components installed therein.
2. Background of the Invention
Conventional approaches to key switches for keyboards have aimed at reducing the dimensions of the key switches, so that they may be used on notebook computer keyboards. Therefore, almost all designs employ crossed linking members to transmit the pressing operation of key switches. But there should remain a detectable feeling of two-step touch control during the key switch pressing operation. Therefore, connecting rods or other such constructions are normally used on key switches to enable the feeling of two-step touch control, but they are normally too sophisticated to enable convenient assembly.
Furthermore, for smooth restoration to the original position after the pressing force applied on the key switch is removed, normally there is a rubber component installed in the key switch, the rubber component serving to provide the resilience required to restore the key switch to its original position. For the purpose of providing the feeling of two-step touch control and restoring the key switch to its normal position, then, sophisticated construction is required, leading to increased man hours and difficulty of labor in the assembly process, as well as to increased costs.
The primary object of the present invention is to provide a key switch comprising a key base, a key cap, a first linking member and a second linking member that cross and inter-link with each other, and a flexible member that is installed on the first linking member. The second linking member has a pressing member that maintains contact with the flexible member. When the key switch is pressed down, the pressing lever depresses the flexible member downward, causing the flexible member to change its shape from an outward curve to a straight line, then to an inward curve, producing the feeling of two degrees of resistive force. When the pressing force is removed, the resilience of the flexible member drives the key switch upward to restore its original, normal position.
Because the flexible member is employed on the key switch to produce the feeling of two-step touch control and restore the key switch to its original position, the need for installation of any rubber component, or for a sophisticated construction is eliminated. This leads to reduced production costs, simplified assembly processes, and extended service life.